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Recombinant E.coli LLO/OVA Induces Murine BMDCs Maturation via TLR4 and NOD1 Receptor and Promotes Specific Cytotoxic T Cell Immunity
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作者 MAN XU MING-SHEN DAI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第5期350-356,共7页
Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their ... Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their Toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) receptor signalling pathway were examined by superarray hybridization;and the priming effect of the vaccine activated BMDCs on CD4+T and CD8+T was determined by [3H]thymidine uptake and ELISA,the tumor cytotoxic effect of activated CD8+T cells was determined by cytotoxic assay.Results After BMDCs were activated by E.coli LLO/OVA via TLR4,NOD1 receptor and NF-κB signalling pathway,the expression of their surface molecules including MHC class Ⅰ,MHC class Ⅱ,CD40,CD80 and CD86 significantly up-regulated;the secretion of IL-12 and IFN-? increased also.The mature BMDCs stimulated the allergic CD4+T and CD8+T cells proliferation and their IL-2 and IFN-γ secretion,and the activated CD8+T cells effectively killed B16-OVA melanoma cells and RMA-S/OVA lymphoma cells in vitro.Conclusion E.coli LLO/OVA is effective in inducing BMDCs maturation via activating TLR4 and NOD1 receptor signalling pathway and promoting specific anti-tumor T cell immunity in vitro. 展开更多
关键词 Bone marrow-derived dendritic cells BMDCs Recombinant Escherichia coli Toll-like receptor (TLR) Nucleotide-binding oligomerization domain (NOD) CD8+T cells
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Performance Evaluation of Antenna Receive Diversity in SlMO-OFDM System over Rayleigh Fading Channel
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作者 Ripan Kumar Roy Tushar Kanti Roy 《Computer Technology and Application》 2013年第7期364-373,共10页
This paper represents a comparative performance evaluation of different diversity combining techniques for a SIMO-OFDM (single-input-multiple-output orthogonal frequency division multiplexing) system over Rayleigh f... This paper represents a comparative performance evaluation of different diversity combining techniques for a SIMO-OFDM (single-input-multiple-output orthogonal frequency division multiplexing) system over Rayleigh fading channel. OFDM is a key technique for achieving high data rates and spectral efficiency requirements for wireless communication systems. But in scattering environment, the system performances are severely degraded by the effects of multipath fading and inter-symbol interference. In wireless communication systems, antenna diversity is an important technique to combat multipath fading in order to improve the system performance and increase the channel capacity. In this paper, the performance of different diversity combining techniques-SC (selection combining), EGC (equal gain combining) and MRC (maximal ratio combining) has been analyzed and compared in terms of SNR (signal to noise ratio) and BER (bit error rate) probability. The simulation results show that the maximal ratio combining technique provides maximum performance improvement relative to all other combining schemes by maximizing the SNR of SIMO-OFDM system at the combiner output. The analytic expressions of error probability and effective bit energy to noise ratio correlated with BPSK (binary phase shift keying) modulation have been derived and formulated for N-branch SC, EGC and MRC schemes. The BER characteristics for all three combining techniques are simulated in MATLAB (matrix laboratory) tool box for varying bit energy to noise ratio. Our results also derives that SNR can be improved if the number of receiving antenna is increased, which in turn reduces BER over a Rayleigh fading channel. 展开更多
关键词 OFDM antenna diversity SC EGC MRC Rayleigh fading BER SNR IBI ICI FFT BPSK modulation.
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Zero Energy Hotels and Sustainable Mobility in the Islands of Aegean Sea (Greece)
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作者 Giuseppe Maria Perfetto Francesco Paolo Lamacchia 《International Journal of Clean Coal and Energy》 2016年第2期23-36,共14页
The goal of this work is to evaluate and to give evidence to innovative and sustainable technologies applied in the construction industry to carry out self-sufficient energy and to use the surplus energy for the produ... The goal of this work is to evaluate and to give evidence to innovative and sustainable technologies applied in the construction industry to carry out self-sufficient energy and to use the surplus energy for the production of hydrogen vector. An architectural integration design along with high technological systems is performed. The intermittency of renewable energy sources along with climatic conditions dependency imposes to store the energy produced, since it is clean and having a big calorific value: the hydrogen vector is currently the better energy carrier. The energy to obtain hydrogen by dissociation of water is supplied by a photovoltaic (PV) system. Through the computations of the annual energy balance between building’s demand and supply energy, it is shown that the extra energy produced by the solar generation system is used also for the hydrogen sustainable mobility. The renewable systems, model’s design and case study are tackled for the bigger one of the Dodecanese islands in the South Aegean Sea: Rhodes (Rodos). The Zero energy building’s integrative design-based approach, applied to the Hotel Buildings type industry is targeted to have new hotels buildings, in the Mediterranean typical warm climate, with zero energy consumption. The designers, authors of this work, have studied a real case or pilot project of an hotel, in the resort formula, suitable to the Greek landscape, showcasing technologies and innovations supporting environmental sustainability, energy efficiency, use of renewable energy, electricity storage by fuel cells that are tools particularly applicable to hotel facility [1]. The feasibility of this case study or pilot project is aligned jointly to the target of Zero Emission and Energy Efficiency EU Policy, as imposed by EU Directives. The strategic position of Rhodes in a geographical point full of sun and wind renewable energy power, enables to ensure the clean energy production, the current interesting development of the hydrogen as energy vector in the buildings [2] and also to satisfy the demand of tourists’ accommodation by having at the same time zero energy costs. Moreover, the presence in the island of the best example worldwide of ancient and sustainable built environment (UNESCO World Heritage site), represents also the best motivation to give witness there of a zero impact environmental urban development through the adoption of these achieved scientific results for a major success of Zero Energy Buildings. 展开更多
关键词 Zero Energy Buildings ZEB nZEB Design Zero Energy Cities nZEH Hydrogen Sustainable Building ZEH Sustainable Mobility
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Decentralised dynamic high-gain scaling-based output-feedback control of large-scale non-linear interconnected systems with delays 被引量:3
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作者 P.Krishnamurthy F.Khorrami 《Journal of Control and Decision》 EI 2014年第4期257-282,共26页
A general class of non-linear large-scale interconnected systems is considered,wherein each subsystem is comprised of a nominal part in a general strict-feedback-like structure and a set of appended dynamics.Parametri... A general class of non-linear large-scale interconnected systems is considered,wherein each subsystem is comprised of a nominal part in a general strict-feedback-like structure and a set of appended dynamics.Parametric and functional uncertainties and time delays are allowed throughout the overall system structure including the nominal strictfeedback-like parts and appended dynamics of each subsystem as well as the non-linear subsystem interconnections.The controller design is based on the dual dynamic highgain scaling technique and provides a robust adaptive delay-independent globally stabilising decentralised output-feedback controller.The disturbance attenuation properties of the proposed output-feedback decentralised controller to an exogenous disturbance input are also analysed and specific conditions under which properties such as Input-toOutput-practical-Stability and asymptotic stabilisation are attained are also discussed. 展开更多
关键词 non-linear decentralised control large-scale interconnected systems uncertain systems delay systems global stabilisation robust non-linear control
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北极航道跟航模式下船-船碰撞几何概率计算模型
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作者 罗佳炫 罗小芳 +1 位作者 昝英飞 ZHANG Ningbo 《船舶工程》 北大核心 2025年第8期70-76,共7页
[目的]随着北极航运业的快速发展,商船编队航行时船-船碰撞事故频发的问题成为各界关注的焦点,其中跟航模式下船-船碰撞事故发生概率是关键问题之一。[方法]考虑船舶、环境和人员等因素,基于跟驰理论构建了考虑碎冰阻力影响的船-船碰撞... [目的]随着北极航运业的快速发展,商船编队航行时船-船碰撞事故频发的问题成为各界关注的焦点,其中跟航模式下船-船碰撞事故发生概率是关键问题之一。[方法]考虑船舶、环境和人员等因素,基于跟驰理论构建了考虑碎冰阻力影响的船-船碰撞几何模型;基于可靠指标理论,将跟航模式下制动后的船-船状态划分为危险、极限与安全状态,推导了跟航安全的极限状态方程,进而建立了跟航模式下船-船碰撞几何概率计算模型。[结果]基于永盛轮北极航行案例数据开展分析,结果表明:所构建的模型能够有效评估船-船碰撞事故发生概率,船-船碰撞概率与海冰密集度、驾驶员反应时长成正比,而与船间安全余量呈反比。[结论]该碰撞概率计算模型可为跟航模式下的安全管理提供坚实的理论支持和决策依据。 展开更多
关键词 碰撞概率 跟航模式 船-船碰撞 几何概率
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UV-assisted ratiometric fiuorescence sensor for one-pot visual detection of Salmonella 被引量:1
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作者 Ren Shen Yanmei Fang +4 位作者 Chunxiao Yang Quande Wei Pui-In Mak Rui P.Martins Yanwei Jia 《Chinese Chemical Letters》 2025年第4期593-599,共7页
Rapid diagnosis of Salmonella is crucial for the effective control of food safety incidents, especially in regions with poor hygiene conditions. Polymerase chain reaction(PCR), as a promising tool for Salmonella detec... Rapid diagnosis of Salmonella is crucial for the effective control of food safety incidents, especially in regions with poor hygiene conditions. Polymerase chain reaction(PCR), as a promising tool for Salmonella detection, is facing a lack of simple and fast sensing methods that are compatible with field applications in resource-limited areas. In this work, we developed a sensing approach to identify PCR-amplified Salmonella genomic DNA with the naked eye in a snapshot. Based on the ratiometric fiuorescence signals from SYBR Green Ⅰ and Hydroxyl naphthol blue, positive samples stood out from negative ones with a distinct color pattern under UV exposure. The proposed sensing scheme enabled highly specific identification of Salmonella with a detection limit at the single-copy level. Also, as a supplement to the intuitive naked-eye visualization results, numerical analysis of the colored images was available with a smartphone app to extract RGB values from colored images. This work provides a simple, rapid, and user-friendly solution for PCR identification, which promises great potential in molecular diagnosis of Salmonella and other pathogens in field. 展开更多
关键词 Bacteria detection Polymerase chain reaction Naked-eye visualization Ratiometric fiuorescence Smartphone app
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基于试验验证下的FRP筋与混凝土粘结滑移界面关系有限元模型的建立方法
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作者 张羽 傅丰 +1 位作者 郑吉丰 陈宇飞 《建筑结构》 北大核心 2025年第12期56-66,共11页
为得到一种较为准确的纤维增强复合材料筋(FRP筋)与混凝土粘结滑移界面关系有限元模型的建立方法,进行了FRP筋混凝土试件的中心拉拔试验。运用通用有限元软件ABAQUS建立精细化的有限元模型,模拟FRP筋混凝土静力拉拔试验。通过在ABAQUS... 为得到一种较为准确的纤维增强复合材料筋(FRP筋)与混凝土粘结滑移界面关系有限元模型的建立方法,进行了FRP筋混凝土试件的中心拉拔试验。运用通用有限元软件ABAQUS建立精细化的有限元模型,模拟FRP筋混凝土静力拉拔试验。通过在ABAQUS中设置摩擦力、过盈量、粘结力三种作用模块模拟出FRP筋与混凝土界面粘结力中的表面摩擦力、机械咬合力和化学胶结力作用。按照与试验相同的加载条件和试验工况在ABAQUS模型中设置荷载条件后运行模型,并提取出模拟结果后与试验结果相对照。结果表明:模拟结果与试验结果吻合性较好,模拟破坏模态与试验破坏模态亦相近。验证了FRP筋与混凝土粘结滑移界面关系有限元模型建立方法的正确性和FRP筋与混凝土界面关系参数取值的正确性。 展开更多
关键词 FRP筋 粘结滑移性能 拉拔试验 数值模拟 摩擦 过盈量 粘结力
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欧洲TTF期货多因子交易策略分析
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作者 茹毅鹏 《当代石油石化》 2025年第7期24-28,共5页
欧洲天然气价格日益成为全球天然气市场风向标。深入分析欧洲天然气市场的影响因素,采用多因子交易策略研究荷兰产权转让设施(TTF)天然气价格指数的变化趋势,从供需基本面和金融技术面两大视角出发,系统梳理影响TTF天然气价格波动的多... 欧洲天然气价格日益成为全球天然气市场风向标。深入分析欧洲天然气市场的影响因素,采用多因子交易策略研究荷兰产权转让设施(TTF)天然气价格指数的变化趋势,从供需基本面和金融技术面两大视角出发,系统梳理影响TTF天然气价格波动的多种变量,全面把握价格动态。研究发现,库存变化对TTF天然气价格的影响在10天周期内最为显著,煤炭价格与TTF天然气价格的正向替代关系在50天周期内最为明显,而天气和供应变化分别在20天和100天周期内影响显著。在金融技术面因子中,期限结构和基差动量因子在5天周期内影响突出,亚欧价差因子在20天周期内影响显著。基于此剖析了2024年以来TTF天然气价格波动的原因,并为2025年与欧洲的天然气交易提出策略建议。 展开更多
关键词 天然气 多因子 欧洲 天然气价格 交易策略
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Visual Perception and Adaptive Scene Analysis with Autonomous Panoptic Segmentation
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作者 Darthy Rabecka V Britto Pari J Man-Fai Leung 《Computers, Materials & Continua》 2025年第10期827-853,共27页
Techniques in deep learning have significantly boosted the accuracy and productivity of computer vision segmentation tasks.This article offers an intriguing architecture for semantic,instance,and panoptic segmentation... Techniques in deep learning have significantly boosted the accuracy and productivity of computer vision segmentation tasks.This article offers an intriguing architecture for semantic,instance,and panoptic segmentation using EfficientNet-B7 and Bidirectional Feature Pyramid Networks(Bi-FPN).When implemented in place of the EfficientNet-B5 backbone,EfficientNet-B7 strengthens the model’s feature extraction capabilities and is far more appropriate for real-world applications.By ensuring superior multi-scale feature fusion,Bi-FPN integration enhances the segmentation of complex objects across various urban environments.The design suggested is examined on rigorous datasets,encompassing Cityscapes,Common Objects in Context,KITTI Karlsruhe Institute of Technology and Toyota Technological Institute,and Indian Driving Dataset,which replicate numerous real-world driving conditions.During extensive training,validation,and testing,the model showcases major gains in segmentation accuracy and surpasses state-of-the-art performance in semantic,instance,and panoptic segmentation tasks.Outperforming present methods,the recommended approach generates noteworthy gains in Panoptic Quality:+0.4%on Cityscapes,+0.2%on COCO,+1.7%on KITTI,and+0.4%on IDD.These changes show just how efficient it is in various driving circumstances and datasets.This study emphasizes the potential of EfficientNet-B7 and Bi-FPN to provide dependable,high-precision segmentation in computer vision applications,primarily autonomous driving.The research results suggest that this framework efficiently tackles the constraints of practical situations while delivering a robust solution for high-performance tasks involving segmentation. 展开更多
关键词 Panoptic segmentation multi-scale features efficient net-B7 Feature Pyramid Network
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Transformers for Multi-Modal Image Analysis in Healthcare
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作者 Sameera V Mohd Sagheer Meghana K H +2 位作者 P M Ameer Muneer Parayangat Mohamed Abbas 《Computers, Materials & Continua》 2025年第9期4259-4297,共39页
Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status... Integrating multiple medical imaging techniques,including Magnetic Resonance Imaging(MRI),Computed Tomography,Positron Emission Tomography(PET),and ultrasound,provides a comprehensive view of the patient health status.Each of these methods contributes unique diagnostic insights,enhancing the overall assessment of patient condition.Nevertheless,the amalgamation of data from multiple modalities presents difficulties due to disparities in resolution,data collection methods,and noise levels.While traditional models like Convolutional Neural Networks(CNNs)excel in single-modality tasks,they struggle to handle multi-modal complexities,lacking the capacity to model global relationships.This research presents a novel approach for examining multi-modal medical imagery using a transformer-based system.The framework employs self-attention and cross-attention mechanisms to synchronize and integrate features across various modalities.Additionally,it shows resilience to variations in noise and image quality,making it adaptable for real-time clinical use.To address the computational hurdles linked to transformer models,particularly in real-time clinical applications in resource-constrained environments,several optimization techniques have been integrated to boost scalability and efficiency.Initially,a streamlined transformer architecture was adopted to minimize the computational load while maintaining model effectiveness.Methods such as model pruning,quantization,and knowledge distillation have been applied to reduce the parameter count and enhance the inference speed.Furthermore,efficient attention mechanisms such as linear or sparse attention were employed to alleviate the substantial memory and processing requirements of traditional self-attention operations.For further deployment optimization,researchers have implemented hardware-aware acceleration strategies,including the use of TensorRT and ONNX-based model compression,to ensure efficient execution on edge devices.These optimizations allow the approach to function effectively in real-time clinical settings,ensuring viability even in environments with limited resources.Future research directions include integrating non-imaging data to facilitate personalized treatment and enhancing computational efficiency for implementation in resource-limited environments.This study highlights the transformative potential of transformer models in multi-modal medical imaging,offering improvements in diagnostic accuracy and patient care outcomes. 展开更多
关键词 Multi-modal image analysis medical imaging deep learning image segmentation disease detection multi-modal fusion Vision Transformers(ViTs) precision medicine clinical decision support
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Multiscale modeling of thermo-hydromechanical behavior of clayey rocks and application to geological disposal of radioactive waste
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作者 Jianfu Shao Zhan Yu Minh-Ngoc Vu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期1-19,共19页
This work is devoted to numerical analysis of thermo-hydromechanical problem and cracking process in saturated porous media in the context of deep geological disposal of radioactive waste.The fundamental background of... This work is devoted to numerical analysis of thermo-hydromechanical problem and cracking process in saturated porous media in the context of deep geological disposal of radioactive waste.The fundamental background of thermo-poro-elastoplasticity theory is first summarized.The emphasis is put on the effect of pore fluid pressure on plastic deformation.A micromechanics-based elastoplastic model is then presented for a class of clayey rocks considered as host rock.Based on linear and nonlinear homogenization techniques,the proposed model is able to systematically account for the influences of porosity and mineral composition on macroscopic elastic properties and plastic yield strength.The initial anisotropy and time-dependent deformation are also taken into account.The induced cracking process is described by using a non-local damage model.A specific hybrid formulation is proposed,able to conveniently capture tensile,shear and mixed cracks.In particular,the influences of pore pressure and confining stress on the shear cracking mechanism are taken into account.The proposed model is applied to investigating thermo-hydromechanical responses and induced damage evolution in laboratory tests at the sample scale.In the last part,an in situ heating experiment is analyzed by using the proposed model.Numerical results are compared with experimental data and field measurements in terms of temperature variation,pore fluid pressure change and induced damaged zone. 展开更多
关键词 Radioactive waste Geological disposal Thermo-hydromechanical coupling Clayey rocks Damage and cracking Phase-field modeling
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Performance Evaluation of Dynamic Adaptive Routing(DAR)for Unmanned Aerial Vehicle(UAV)Networks
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作者 Khadija Slimani Samira Khoulji +1 位作者 Hamed Taherdoost Mohamed Larbi Kerkeb 《Computers, Materials & Continua》 2025年第11期4115-4132,共18页
Reliable and efficient communication is essential for Unmanned Aerial Vehicle(UAV)networks,especially in dynamic and resource-constrained environments such as disaster management,surveillance,and environmental monitor... Reliable and efficient communication is essential for Unmanned Aerial Vehicle(UAV)networks,especially in dynamic and resource-constrained environments such as disaster management,surveillance,and environmental monitoring.Frequent topology changes,high mobility,and limited energy availability pose significant challenges to maintaining stable and high-performance routing.Traditional routing protocols,such as Ad hoc On-Demand Distance Vector(AODV),Load-Balanced Optimized Predictive Ad hoc Routing(LB-OPAR),and Destination-Sequenced Distance Vector(DSDV),often experience performance degradation under such conditions.To address these limitations,this study evaluates the effectiveness of Dynamic Adaptive Routing(DAR),a protocol designed to adapt routing decisions in real time based on network dynamics and resource constraints.The research utilizes the Network Simulator 3(NS-3)platform to conduct controlled simulations,measuring key performance indicators such as latency,Packet Delivery Ratio(PDR),energy consumption,and throughput.Comparative analysis reveals that DAR consistently outperforms conventional protocols,achieving a 20%-30% reduction in latency,a 25% decrease in energy consumption,and marked improvements in throughput and PDR.These results highlight DAR’s ability to maintain high communication reliability while optimizing resource usage in challenging operational scenarios.By providing empirical evidence of DAR’s advantages in highly dynamic UAV network environments,this study contributes to advancing adaptive routing strategies.The findings not only validate DAR’s robustness and scalability but also lay the groundwork for integrating artificial intelligence-driven decision-making and real-world UAV deployment.Future work will explore cross-layer optimization,multi-UAV coordination,and experimental validation in field trials,aiming to further enhance communication resilience and energy efficiency in next-generation aerial networks. 展开更多
关键词 Dynamic adaptive routing(DAR) UAV networks NS-3 simulation packet delivery ratio(PDR) energy efficiency
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Cardiovascular Sound Classification Using Neural Architectures and Deep Learning for Advancing Cardiac Wellness
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作者 Deepak Mahto Sudhakar Kumar +6 位作者 Sunil KSingh Amit Chhabra Irfan Ahmad Khan Varsha Arya Wadee Alhalabi Brij B.Gupta Bassma Saleh Alsulami 《Computer Modeling in Engineering & Sciences》 2025年第6期3743-3767,共25页
Cardiovascular diseases(CVDs)remain one of the foremost causes of death globally;hence,the need for several must-have,advanced automated diagnostic solutions towards early detection and intervention.Traditional auscul... Cardiovascular diseases(CVDs)remain one of the foremost causes of death globally;hence,the need for several must-have,advanced automated diagnostic solutions towards early detection and intervention.Traditional auscultation of cardiovascular sounds is heavily reliant on clinical expertise and subject to high variability.To counter this limitation,this study proposes an AI-driven classification system for cardiovascular sounds whereby deep learning techniques are engaged to automate the detection of an abnormal heartbeat.We employ FastAI vision-learner-based convolutional neural networks(CNNs)that include ResNet,DenseNet,VGG,ConvNeXt,SqueezeNet,and AlexNet to classify heart sound recordings.Instead of raw waveform analysis,the proposed approach transforms preprocessed cardiovascular audio signals into spectrograms,which are suited for capturing temporal and frequency-wise patterns.The models are trained on the PASCAL Cardiovascular Challenge dataset while taking into consideration the recording variations,noise levels,and acoustic distortions.To demonstrate generalization,external validation using Google’s Audio set Heartbeat Sound dataset was performed using a dataset rich in cardiovascular sounds.Comparative analysis revealed that DenseNet-201,ConvNext Large,and ResNet-152 could deliver superior performance to the other architectures,achieving an accuracy of 81.50%,a precision of 85.50%,and an F1-score of 84.50%.In the process,we performed statistical significance testing,such as the Wilcoxon signed-rank test,to validate performance improvements over traditional classification methods.Beyond the technical contributions,the research underscores clinical integration,outlining a pathway in which the proposed system can augment conventional electronic stethoscopes and telemedicine platforms in the AI-assisted diagnostic workflows.We also discuss in detail issues of computational efficiency,model interpretability,and ethical considerations,particularly concerning algorithmic bias stemming from imbalanced datasets and the need for real-time processing in clinical settings.The study describes a scalable,automated system combining deep learning,feature extraction using spectrograms,and external validation that can assist healthcare providers in the early and accurate detection of cardiovascular disease.AI-driven solutions can be viable in improving access,reducing delays in diagnosis,and ultimately even the continued global burden of heart disease. 展开更多
关键词 Healthy society cardiovascular system SPECTROGRAM FastAI audio signals computer vision neural network
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Potential of adaptive co-management in restoring socio-ecological functions of degraded community forests in temperate Himalaya, India
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作者 Kottapalli Sreenivasa RAO Rajeev Lochan SEMWAL +3 位作者 Ajay MALETHA Sunil NAUTIYAL Rakesh Kumar MAIKHURI Krishna Gopal SAXENA 《Journal of Mountain Science》 2025年第3期860-872,共13页
Scarcity of empirical studies turning the concepts into cost-effective practices is a barrier in achieving the desired trajectory and scale of ecosystem restoration.The present study aimed to assess(i)potential of tre... Scarcity of empirical studies turning the concepts into cost-effective practices is a barrier in achieving the desired trajectory and scale of ecosystem restoration.The present study aimed to assess(i)potential of tree-bamboo-medicinal herb mixed plantation founded on the concept of adaptive comanagement in restoration of degraded community forest in a temperate village of Indian Himalaya and(ii)persistence of offer of local people to voluntarily maintain and expand the trial after its economic benefit/cost ratio became>1.0.Biodiversity,carbon stock and economic benefits were assessed in the restored forest 1,3 and 10 years after 7-year-long funding phase(i.e.,8,10 and 20 years after initial planting in 1991),and other land uses in the village landscape.Significant economic loss occurred from gregarious flowering induced mass mortality of bamboo in the 2nd year after funding phase but it was outweighed by the gain from walnut fruiting.People maintained recovery by transplanting Nepalese Alder(Alnus nepalensis)in gaps.The 20-year-old restored forest land had 17%of aboveground and 75%of belowground carbon stocks,and 39%of flowering species present in the intact forest.Restored forest had only four of the eight Near-threatened/Threatened species present in intact forest.Further,intact forest was monetarily the most efficient land use despite absence of payments for its ecosystem services.People did not expand the trial or medicinal plant cultivation in farms induced by it.They abandoned cropping in 39%farm area and leased 24%abandoned area to a company.Flowering plant species richness and carbon stocks changed at the ecosystem scale but not at the village landscape scale.Emission from agricultural abandonment nullified carbon sequestration by forest restoration.Community forest restoration should render both material/monetary and nonmaterial/non-monetary benefits to people.Cultural landscapes should be taken as spatial units for ecosystem restoration planning,monitoring and evaluation. 展开更多
关键词 BAMBOO BIODIVERSITY Carbon sequestration Climate change Medicinal herbs Threatened species
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Quantifying unseen woody biomass and diversity in understorey trees and shrubs at the extremes of water availability in the Miombo ecoregion
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作者 Hermane Diesse John L.Godlee +7 位作者 Nichola Knox Jonathan Muledi Leena Naftal David Nkulu Ben Nkomba Gabriel Uusiku Kyle Dexter Vera De Cauwer 《Forest Ecosystems》 2025年第3期482-494,共13页
The Miombo ecoregion covers eastern and southern Africa,with variations in plant species composition,structure,and biomass across a broad precipitation gradient.Most studies of woody plant communities focus exclusivel... The Miombo ecoregion covers eastern and southern Africa,with variations in plant species composition,structure,and biomass across a broad precipitation gradient.Most studies of woody plant communities focus exclusively on larger overstorey trees(≥5 or≥10cm stem diameter),overlooking the contribution of small trees and shrubs in the understorey,which can comprise a significant portion of total biomass and diversity.Here,we evaluate the contribution of both large overstorey and small understorey woody plants to species diversity and above-ground biomass(AGB),with 17 plots(0.5-1ha)across five sites representing both extremes of rainfall gradient spanning the Miombo ecoregion,in northeast Namibia(500-700mm mean annual precipitation,MAP)and southern Democratic Republic of Congo(DRC)(>1,200mm MAP).Mean AGB per site ranged from 21 to 119Mg·ha^(-1),increasing with rainfall,while the proportional AGB contribution of small trees,saplings,and shrubs decreased.In dry Namibia,small trees,saplings,and shrubs(<5cm DBH)contributed up to 28.2%of total AGB(mean±standard deviation:18.3%±3.4%),whereas in wet DRC,they contributed only up to 2.5%(2.3%±1.4%).Namibian sites,on average,contained a large proportion of woody species diversity exclusively in small trees and shrubs(<5cm DBH),with 55 species representing 59.4%of the total diversity.In contrast,DRC sites had higher overall small woody plant diversity(66 species)but fewer species found exclusively as small individuals(25.2%),with many saplings that grow to larger trees.Understorey composition also differed,with saplings of overstorey trees dominating in DRC,while shrubs dominated in Namibia.Our findings show that woody biomass and diversity in dry woodlands are substantially underestimated when studies focus only on larger trees.This highlights the need to consider all woody vegetation to better understand woody plant diversity and biomass variation. 展开更多
关键词 Miombo woodlands Plant diversity Overstorey UNDERSTOREY Biomass SHRUBS Stand structure
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RECENT ADVANCES IN RESEARCH AND FORECASTING OF TROPICAL CYCLONE TRACK, INTENSITY, AND STRUCTURE AT LANDFALL 被引量:4
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作者 MARIE-DOMINIQUE LEROUX KIMBERLY WOOD +7 位作者 RUSSELL L.ELSBERRY ESPERANZA O.CAYANAN ERIC HENDRICKS MATTHEW KUCAS PETER OTTO ROBERT ROGERS BUCK SAMPSON ZIFENG YU 《Tropical Cyclone Research and Review》 2018年第2期85-105,共21页
This review prepared for the fourth International Workshop on Tropical Cyclone Landfall Processes(IWTCLP-4) summarizes the most recent(2015-2017) theoretical and practical knowledge in the field of tropical cyclone(TC... This review prepared for the fourth International Workshop on Tropical Cyclone Landfall Processes(IWTCLP-4) summarizes the most recent(2015-2017) theoretical and practical knowledge in the field of tropical cyclone(TC) track, intensity, and structure rapid changes at or near landfall. Although the focus of IWTCLPIV was on landfall, this summary necessarily embraces the characteristics of storms during their course over the ocean prior to and leading up to landfall. In the past few years, extremely valuable observational datasets have been collected for TC forecasting guidance and research studies using both aircraft reconnaissance and new geostationary or low-earth orbiting satellites at high temporal and spatial resolution. Track deflections for systems near complex topography such as that of Taiwan and La Réunion have been further investigated, and advanced numerical models with high spatial resolution necessary to predict the interaction of the TC circulation with steep island topography have been developed. An analog technique has been designed to meet the need for longer range landfall intensity forecast guidance that will provide more time for emergency preparedness. Probabilistic track and intensity forecasts have also been developed to better communicate on forecast uncertainty. Operational practices of several TC forecast centers are described herein and some challenges regarding forecasts and warnings for TCs making landfall are identified. This review concludes with insights from both researchers and forecasters regarding future directions to improve predictions of TC track, intensity, and structure at landfall. 展开更多
关键词 tropical CYCLONE track INTENSITY STRUCTURE LANDFALL RAPID INTENSIFICATION RAPID changes
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An efficient approach for anti-jamming in IRNSS receivers using improved PSO based parametric wavelet packet thresholding
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作者 Jacob Silva Lorraine Kambham Madhu Ramarakula 《Satellite Navigation》 2022年第3期51-70,I0003,共21页
The Indian Regional Navigation Satellite System provides accurate positioning service to the users within and around India,extending up to 1500 km.However,when a receiver encounters a Continuous Wave Interference,its ... The Indian Regional Navigation Satellite System provides accurate positioning service to the users within and around India,extending up to 1500 km.However,when a receiver encounters a Continuous Wave Interference,its positioning accuracy degrades,or sometimes it even fails to work.Wavelet Packet Transform(WPT)is the most widely used technique for anti-jamming in Global Navigation Satellite System receivers.But the conventional method suffers from threshold drifting and employs inflexible thresholding functions.So,to address these issues,an efficient approach using Improved Particle Swarm Optimization based Parametric Wavelet Packet Thresholding(IPSO-PWPT)is proposed.Firstly,a new parameter adaptive thresholding function is constructed.Then,a new form of inertia weight is presented to enhance the performance of PSO.Later,IPSO is used to optimize the key parameters of WPT.Finally,the implementation of the IPSO-PWPT anti-jamming algorithm is discussed.The performance of the proposed technique is evaluated for various performance metrics in four jamming environments.The evaluation results manifest the proposed method’s efficacy compared to the conventional WPT in terms of anti-jamming capability.Also,the results show the ability of the new thresholding function to process various signals effectively.Furthermore,the findings reveal that the improved PSO outperforms the variants of PSO. 展开更多
关键词 Continuous wave interference(CWI) IRNSS Particle swarm optimization(PSO) Wavelet packet transform(WPT)
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高精度光纤时间频率传递及集成化技术(特邀) 被引量:1
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作者 陈建平 刘涛 +1 位作者 B.M.A.Rahman 胡亮 《光学学报(网络版)》 2024年第2期20-31,共12页
高稳定时间频率(简称“时频”)传递是时频系统两种核心技术之一。基于光纤可实现高精度、大范围传递,是地面时频传递的最佳选择。本文介绍光纤时频传递基本原理,以光纤光学频率传递为例,深入阐述了系统噪声补偿方法。针对目前时频传递... 高稳定时间频率(简称“时频”)传递是时频系统两种核心技术之一。基于光纤可实现高精度、大范围传递,是地面时频传递的最佳选择。本文介绍光纤时频传递基本原理,以光纤光学频率传递为例,深入阐述了系统噪声补偿方法。针对目前时频传递设备因采用分立光电子器件而存在的不足,探索研究了光电子集成芯片设计方法,展示了集成化的优势。最后,总结了国内外光纤时频传递研究进展,并对其未来发展进行了展望。 展开更多
关键词 时间/频率基准 时频传递 光纤 集成芯片
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来特莫韦用于异基因造血干细胞移植后巨细胞病毒感染和巨细胞病毒病预防的成本-效用分析
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作者 吴畏 张潇 +1 位作者 Jootun Murvin 贺小宁 《中国新药杂志》 CAS CSCD 北大核心 2024年第16期1737-1744,共8页
目的:从中国医疗卫生体系角度出发,评价来特莫韦(注射剂与片剂序贯治疗)联合抢先治疗(pre-emptive antiviral therapy,PET)相比于仅接受PET,用于异基因造血干细胞移植(allogeneic hematopoietic stem cell transplantation,Allo-HSCT)... 目的:从中国医疗卫生体系角度出发,评价来特莫韦(注射剂与片剂序贯治疗)联合抢先治疗(pre-emptive antiviral therapy,PET)相比于仅接受PET,用于异基因造血干细胞移植(allogeneic hematopoietic stem cell transplantation,Allo-HSCT)后巨细胞病毒(cytomegalovirus,CMV)血清阳性成人受者(R+)预防CMV感染和CMV病的成本-效果。方法:构建短期决策树模型联合长期马尔可夫模型,模拟患者临床产出与成本。模型中的临床参数、效用参数来源于来特莫韦临床试验P001(NCT02137772)和已发表文献,成本数据来源于公开数据库及临床专家调研结果,同时开展单因素敏感性分析和概率敏感性分析。结果:与仅接受PET、不接受CMV预防相比,采用来特莫韦CMV预防联合PET的增量质量调整生命年(quality-adjusted life years,QALYs)为0.44,增量成本-效果比(incremental cost-effectiveness ratio,ICER)为59871元·QALY^(-1),远低于2022年3倍中国人均GDP,经济性良好。概率敏感性分析结果显示,基础分析结果稳健。结论:与仅接受PET、不接受CMV预防相比,来特莫韦用于接受Allo-HSCT后CMV血清阳性成人受者(R^(+))预防CMV感染和CMV病具有成本-效果。 展开更多
关键词 来特莫韦 异基因造血干细胞移植 巨细胞病毒 成本-效用分析
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Risk factors for hepatocellular carcinoma associated with hepatitis C genotype 3 infection:A systematic review 被引量:2
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作者 Hamzah Z Farooq Michael James +4 位作者 Jane Abbott Patrick Oyibo Pip Divall Naheed Choudhry Graham R Foster 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1596-1612,共17页
BACKGROUND Hepatitis C virus(HCV)is a blood-borne virus which globally affects around 79 million people and is associated with high morbidity and mortality.Chronic infection leads to cirrhosis in a large proportion of... BACKGROUND Hepatitis C virus(HCV)is a blood-borne virus which globally affects around 79 million people and is associated with high morbidity and mortality.Chronic infection leads to cirrhosis in a large proportion of patients and often causes hepatocellular carcinoma(HCC)in people with cirrhosis.Of the 6 HCV genotypes(G1-G6),genotype-3 accounts for 17.9%of infections.HCV genotype-3 responds least well to directly-acting antivirals and patients with genotype-3 infection are at increased risk of HCC even if they do not have cirrhosis.AIM To systematically review and critically appraise all risk factors for HCC secondary to HCV-G3 in all settings.Consequently,we studied possible risk factors for HCC due to HCV-G3 in the literature from 1946 to 2023.METHODS This systematic review aimed to synthesise existing and published studies of risk factors for HCC secondary to HCV genotype-3 and evaluate their strengths and limitations.We searched Web of Science,Medline,EMBASE,and CENTRAL for publications reporting risk factors for HCC due to HCV genotype-3 in all settings,1946-2023.RESULTS Four thousand one hundred and forty-four records were identified from the four databases with 260 records removed as duplicates.Three thousand eight hundred and eighty-four records were screened with 3514 excluded.Three hundred and seventy-one full-texts were assessed for eligibility with seven studies included for analysis.Of the seven studies,three studies were retrospective case-control trials,two retrospective cohort studies,one a prospective cohort study and one a cross-sectional study design.All were based in hospital settings with four in Pakistan,two in South Korea and one in the United States.The total number of participants were 9621 of which 167 developed HCC(1.7%).All seven studies found cirrhosis to be a risk factor for HCC secondary to HCV genotype-3 followed by higher age(five-studies),with two studies each showing male sex,high alpha feto-protein,directly-acting antivirals treatment and achievement of sustained virologic response as risk factors for developing HCC.CONCLUSION Although,studies have shown that HCV genotype-3 infection is an independent risk factor for end-stage liver disease,HCC,and liver-related death,there is a lack of evidence for specific risk factors for HCC secondary to HCV genotype-3.Only cirrhosis and age have demonstrated an association;however,the number of studies is very small,and more research is required to investigate risk factors for HCC secondary to HCV genotype-3. 展开更多
关键词 Hepatocellular carcinoma Hepatitis C Genotype 3 Systematic review Blood-borne viruses Liver cancer
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